Premium
Decreased brain PME / PDE ratio in bipolar disorder: a preliminary 31 P magnetic resonance spectroscopy study
Author(s) -
Shi XianFeng,
Carlson Paul J,
Sung YoungHoon,
Fiedler Kristen K,
Forrest Lauren N,
Hellem Tracy L,
Huber Rebekah S,
Kim SeongEun,
Zuo Chun,
Jeong EunKee,
Renshaw Perry F,
Kondo Douglas G
Publication year - 2015
Publication title -
bipolar disorders
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.285
H-Index - 129
eISSN - 1399-5618
pISSN - 1398-5647
DOI - 10.1111/bdi.12339
Subject(s) - bipolar disorder , phosphocreatine , chemistry , phosphomonoesters , medicine , frontal lobe , endocrinology , bipolar i disorder , nuclear magnetic resonance , psychology , magnetic resonance imaging , mood , psychiatry , mania , physics , radiology , energy metabolism
Objectives The aim of the present study was to measure brain phosphorus‐31 magnetic resonance spectroscopy ( 31 P MRS ) metabolite levels and the creatine kinase reaction forward rate constant (k f ) in subjects with bipolar disorder ( BD ). Methods Subjects with bipolar euthymia (n = 14) or depression (n = 11) were recruited. Healthy comparison subjects ( HC ) (n = 23) were recruited and matched to subjects with BD on age, gender, and educational level. All studies were performed on a 3‐Tesla clinical magnetic resonance imaging system using a 31 P/ 1 H double‐tuned volume head coil. 31 P spectra were acquired without 1 H‐decoupling using magnetization‐transfer image‐selected in vivo spectroscopy. Metabolite ratios from a brain region that includes the frontal lobe, corpus callosum, thalamus, and occipital lobe are expressed as a percentage of the total phosphorus ( TP ) signal. Brain pH was also investigated. Results Beta‐nucleoside‐triphosphate (β‐ NTP / TP ) in subjects with bipolar depression was positively correlated with k f (p = 0.039, r 2 = 0.39); similar correlations were not observed in bipolar euthymia or HC . In addition, no differences in k f and brain pH were observed among the three diagnostic groups. A decrease in the ratio of phosphomonoesters to phosphodiesters ( PME / PDE ) was observed in subjects with bipolar depression relative to HC (p = 0.032). We also observed a trend toward an inverse correlation in bipolar depression characterized by decreased phosphocreatine and increased depression severity. Conclusions In our sample, k f was not altered in the euthymic or depressed mood state in BD . However, decreased PME / PDE in subjects with bipolar depression was consistent with differences in membrane turnover. These data provide preliminary support for alterations in phospholipid metabolism and mitochondrial function in bipolar depression.